Project summary: Substance use disorders (SUD) are significant contributors to the global burden of disease. Annual direct and indirect economic costs of alcohol, tobacco, and other drugs have been estimated at $500 billion in the United States alone. An estimated 20.2 million Americans are in need of treatment for a SUD, yet fewer than 5% receive specialty treatment. The most frequent point of health care contact in the United States is outpatient primary care. Minnesota ranks 1st in the US for health status and has one of the highest rates of access to primary care in the US. The proposed NorthStar node of the NIDA Clinical Trials Network brings together diverse healthcare delivery models that excel in delivery and research of primary care. Led by internal medicine physicians with practice and research expertise in addiction, the NorthStar node includes: 1) two major non-profit integrated health systems serving more than 1 million Minnesotans through over 100 primary care clinics (HealthPartners and Allina Health); 2) a Federally Qualified Health Center (NorthPoint Health & Wellness Center); 3) an accountable care organization managing the poorest and highest healthcare utilizing populations of Minnesota's most populous county (Hennepin Health); 4) a student health center, which provides primary and behavioral care for the more than 20,000 university students (University of Minnesota's Boynton Health Services); 5) the Institute for Clinical Systems Improvement (ICSI), a non-profit health improvement organization dedicated to developing and implementing quality improvement and best-practices protocols across more than 45 health systems and 8,000 physicians; and 6) the University of Minnesota Clinical and Translational Sciences Institute. In fulfillment of the CTN mission, the NorthStar node will develop (1) models of coordinated chronic care disease management of patients with SUD, (2) risk stratification tools for opiate prescription for chronic pain management in primary care, (3) clinical decision support tools focusing on the treatment of opiate use disorders, (4) integrated models of tobacco cessation treatment and HIV primary care, and (5) effective models to reduce 30-day readmission rates for SUD patients or at-risk users discharged from inpatient general medical settings.